By means of emission computed tomography of patients, we will quantify and localize cerebral biochemical patterns in order to explore the mechanisms underlying human epilepsy, behavior disorders, and other neurological abnormalities. Local cerebral glucose metabolism will be measured by scanning after intravenous injection of F-18-fluorodeoxyglucose. The feasibility will be tested for in vivo receptor assays in man based on emission computed tomography of positron emitter labeled radioligands. Parallel studies will be carried out using quantitative autoradiography of C-14-deoxyglucose and other agents in suitable animal models.